Factor	Sensitivity (%)	Specificity (%)	Positive likelihood ratio	Negative likelihood ratio
Absence of cough	51 to 79	36 to 68	1.1 to 1.7	0.53 to 0.89
Anterior cervical nodes swollen or enlarged	55 to 82	34 to 73	0.47 to 2.9	0.58 to 0.92
Headache	48	50 to 80	0.81 to 2.6	0.55 to 1.1
Myalgia	49	60	1.2	0.84
Palatine petechiae	7	95	1.4	0.98
Pharyngeal exudates	26	88	2	0.85
Streptococcal exposure in past two weeks	19	91	2	0.9
Temperature ≥ 100.9° F (38.3° C)	22 to 58	53 to 92	0.68 to 3.9	0.54 to 1.3
Tonsillar exudates	36	85	2.3	0.76
Tonsillar or pharyngeal exudates	45	75	1.8	0.74